Highcharts热力图单元格未显示颜色问题求助

问题核心原因 #

你的热力图未渲染出单元格颜色，主要是缺少y轴方向的单元格尺寸配置（rowsize）。热力图需要同时定义colsize（x轴方向单元格宽度）和rowsize（y轴方向单元格高度），才能划分出可填充颜色的单元格区域。此外，原代码中用于tooltip的getPointCategoryName函数不适用于datetime类型坐标轴（该轴没有categories属性），会导致提示内容显示异常。

修复方案 #

1. 在series配置中添加rowsize: 24 * 36e5，和已有的colsize保持一致，对应一天的毫秒数，确保y轴方向的单元格能正确划分。
2. 替换tooltip的formatter函数，使用Highcharts.dateFormat格式化datetime类型的坐标轴值，替代无效的getPointCategoryName函数。

修正后的完整代码 #

Highcharts.chart('container', {
  chart: {
    type: 'heatmap',
    marginTop: 40,
    marginBottom: 80,
    plotBorderWidth: 1
  },
  xAxis: {
    type: 'datetime',
    min: Date.UTC(2023, 9, 1),
    max: Date.UTC(2023, 9, 5),
    labels: {
      align: 'center'
    }
  },
  yAxis: {
    type: 'datetime'
  },
  colorAxis: {
    min: 0,
    minColor: '#FFFFFF',
    maxColor: Highcharts.getOptions().colors[0]
  },
  legend: {
    align: 'right',
    layout: 'vertical',
    margin: 0,
    verticalAlign: 'top',
    y: 25,
    symbolHeight: 280
  },
  tooltip: {
    formatter: function() {
      const xDate = Highcharts.dateFormat('%Y-%m-%d', this.point.x);
      const yDate = Highcharts.dateFormat('%Y-%m-%d', this.point.y);
      return `<b>${xDate}</b> sold <br><b>${this.point.value}</b> items on <br><b>${yDate}</b>`;
    }
  },
  series: [{
    data: [
      [Date.UTC(2023, 9, 1), Date.UTC(2023, 9, 1), 15],
      [Date.UTC(2023, 9, 1), Date.UTC(2023, 9, 2), 30],
      [Date.UTC(2023, 9, 1), Date.UTC(2023, 9, 3), 45],
      [Date.UTC(2023, 9, 1), Date.UTC(2023, 9, 4), 60],
      [Date.UTC(2023, 9, 1), Date.UTC(2023, 9, 5), 75],
      [Date.UTC(2023, 9, 2), Date.UTC(2023, 9, 1), 0],
      [Date.UTC(2023, 9, 2), Date.UTC(2023, 9, 2), 15],
      [Date.UTC(2023, 9, 2), Date.UTC(2023, 9, 3), 30],
      [Date.UTC(2023, 9, 2), Date.UTC(2023, 9, 4), 45],
      [Date.UTC(2023, 9, 2), Date.UTC(2023, 9, 5), 60],
      [Date.UTC(2023, 9, 3), Date.UTC(2023, 9, 1), 0],
      [Date.UTC(2023, 9, 3), Date.UTC(2023, 9, 2), 0],
      [Date.UTC(2023, 9, 3), Date.UTC(2023, 9, 3), 15],
      [Date.UTC(2023, 9, 3), Date.UTC(2023, 9, 4), 30],
      [Date.UTC(2023, 9, 3), Date.UTC(2023, 9, 5), 45],
      [Date.UTC(2023, 9, 4), Date.UTC(2023, 9, 1), 0],
      [Date.UTC(2023, 9, 4), Date.UTC(2023, 9, 2), 0],
      [Date.UTC(2023, 9, 4), Date.UTC(2023, 9, 3), 0],
      [Date.UTC(2023, 9, 4), Date.UTC(2023, 9, 4), 15],
      [Date.UTC(2023, 9, 4), Date.UTC(2023, 9, 5), 30],
      [Date.UTC(2023, 9, 5), Date.UTC(2023, 9, 1), 0],
      [Date.UTC(2023, 9, 5), Date.UTC(2023, 9, 2), 0],
      [Date.UTC(2023, 9, 5), Date.UTC(2023, 9, 3), 0],
      [Date.UTC(2023, 9, 5), Date.UTC(2023, 9, 4), 0],
      [Date.UTC(2023, 9, 5), Date.UTC(2023, 9, 5), 15],
    ],
    colsize: 24 * 36e5,
    rowsize: 24 * 36e5, // 添加y轴方向单元格尺寸
    dataLabels: {
      enabled: true,
      color: '#000000'
    }
  }]
});

内容的提问来源于stack exchange，提问作者Francesco Gallarotti